1. Field of the Invention
The invention relates to an active sensor, a method for actuating an active sensor, and to the use of the active sensor in motor vehicles.
2. Description of the Related Art
An active sensor with a two-wire interface is described in document DE 44 34 978 A1, said sensor having a test mode for sensing a critical length of air gap between the sensor and encoder, wherein it is possible to switch over between the normal operating mode and this test mode by changing the operating voltage by virtue of the fact that the sensor is actuated with a serial voltage bit pattern.
Document DE 102 03 483 A1 proposes a wheel speed sensor which can be operated in different modes and has different modes of data transmission, wherein it is possible to switch over between these operating modes by external actuation by means of an additional input.